Valve grinding attachment



pt. 25. 195 L. o. HARMON VALVE GRINDING ATTACHMENT Filed Jan. 19, 1955 Sm gk I N VEN TOR ATTORNEY United States Patent 2,763,966 VALVE GRINDING ATTACHMENT Louis 0. Harmon, Amsterdam, N. Y. Application January 19, 1955, Serial No. 482,781 1 Claim. (Cl. 51-29) This invention relates to a novel attachment for use with a conventional manually supported electric drill, and has for its primary object to provide a valve grinding attachment which will enable engine valves to be quickly and accurately ground with a minimum of'etfort on the part of the operator.

Another object of the invention is toprovide a valve grinding attachment which is capable of. being readily supported with one hand, leaving the other hand free forsupporting the electric drill, and whereby the attachment while in use may be oscillated about the axis of input andoutput shafts thereof for varying the starting and stopping positions of the grinding operation of the valve and to thusaccomplish an overlapping of the ground surfacesto thus insure a more accurate and perfect grinding operation.

Various other objects and advantages of the invention will hereinafter becomemore fully apparent from the following description of the drawing, illustrating a presently preferred embodiment thereof, and wherein:

Figure 1 is a view primarily in top plan and partially in section of the valve grinding attachment, taken substantially along a plane as indicated by the line 1- -1 of Figure 2;

Figure 2 is a sectional View, partly invelevationu taken substantially along a plane as indicated by the line' 2-2 of Figure 1 Figure 3 is:a fragmentary detailed sectional view taken substantially along a plane as indicated by the line 33 of: Figure l", and

Figure 4 is a fragmentary sectional view of a part of the grinding attachment.

Referring more specifically to 'the drawing; 1 the valve grinding attachment in its entirety and comprising the invention is designated generally 6 and includes a housing, designated generally 7, composed of an upper section 8 and a lower section 9. The housing sections 8 and 9 have complementary top and bottom walls 10 and 11, respectively, which are disposed in spaced apart relation to one another. Said walls 10 and 11 have surrounding flanges projecting at right angles therefrom, each extending toward the other section and which are disposed with their edges in abutting engagement, as seen in Figure 2. Said flanges 12 and 13 of the housing sections 8 and 9, respectively, combine to form the surrounding side Wall of the housing 7 and are provided with complementary outwardly projecting cars 14, 15 and 16. Said ears have aligned openings for receiving nut and bolt fastenings 17, by means of which the sections 8 and 9 are secured together to form the housing 7.

Said walls 10 and 11, adjacent a portion of the side wall and remote from the ear 16 are provided with aligned external bosses 18 and 19, respectively, which are tubular and which open into the housing 7 and externally thereof. The bosses 18 and 19 provide bearings for journalling an input shaft 20 and an output shaft 21, respectively. The inner ends of the shafts 20 and 21 extend into the housing chamber 22 and terminate in slightly spaced apart ii-cc relation toone another and have pinions 23 and 24, re spectively, fixed to the adjacent ends thereof and disposed for rotation in the chamber 22. The housing walls 10 and 11 are provided on their inner sides with bosses 25 and 26, respectively, from which project stems 27 and 28, respectively. The distal ends of the stems 27 and 28 terminate at approximately the horizontal center of the chamber 22, as seen in Figure 2. The boss 26 and stem 28 are located substantially nearer the axis of the shafts 20 and 21 than the boss 25 and stem 27.

A ring gear 29 is journalled 0n the stem 27 and is rotatably disposed in the upper housing section 8 and in meshing engagement with the pinion 23. As best seen inFigures 2 and 3, a gear segment 30 is journalled on the stem 28 and has a segmental series of teeth 31 which mesh with the pinion 24 and are concentrically disposed relative to the axis of the stem 28. An arm 32 is formed integral with and projects away from another portion of the gear segment 39which is circumferentially spaced from the ends of the teeth 31. Said arm 32 is loosely disposed in the bottom part of the chamber 22 beneath a part of the ring gear 29 and is provided with an elongated slot 33 which extends longitudinally thereof and which substantially aligns with the stem 28, as seen in Figure3. A crankpin 34 is eccentrically fixed to and depends from the gear 29 and has a lower portion loosely engaging in the slot 33. The distal ends of the stems 27 and 28 may be peened or otherwise flattened, tomaintain the gear 29 and gear segment 38, respectively,.journalled thereon.

The shafts 20 and 21 are provided with complementary threaded portions 35 each of which is engaged by a pair of nuts 36. The nuts 36 are adjusted on the threaded portions 35 so that the inner nut of each pair abuts the distal end of the boss 18 or 19 when the pinions 23 and 24 are disposed substantially coplanar with the gear 29 and gear segment 30, respectively. The input shaft 20 extends upwardly a short distance from its threaded portion 35 and the upper end thereof is adapted to be secured inthe chuck 37 of a conventional electric hand drill, operation of which imparts rotation to said input shaft 20.

One end of an elongated handle 38 rests upon the uppermost car 16 and is secured thereto by the fastening 17 ofsaid ear. The inner end of the handle 38 abuts against apart of the' wall or flange 12 to prevent the handle 38 from swinging relative to the housing]. As seen in Fig ures 1 and 2, the cars 16 and accordingly the inner end of the handle 38 are remotely disposed from the shafts 20 and 21 and with the axis of the handle positioned substantially in alignment with a straight line passing through the shafts 20, 21 and the stems 27 and 28.

The output shaft 21 extends only a short distance beyond its threaded portion 35. An output shaft extension 39 is provided at its upper or inner end with a socket 40 to receive the lower or outer end of the output shaft 21 which is detachably secured therein by a setscrew 41, preferably of the Allen type. The opposite end of the extension shaft 39 is shown provided with a part 42 of noncircular cross section which fits non-turnably into the upper or outer end of the shank 43 of a suction cup 44, which shank has an outwardly opening socket 45 in which the part 42 conformably fits for connecting the suction cup 44 to the extension shaft 39 and accordingly to the output shaft 21 for rotation of said parts as a unit. The suction cup 44- is adapted to be attached by a vacuum or suction engagement to the enlarged upper or outer side 46 of a valve 47. The suction cup 44 is preferably formed of rubber and the lower portion of the shank 43 thereof is preferably provided with a recess 48 which opens into the suction cup and in which is mounted a cup shaped member 49 having an open upper end and containing a pin 58 which extends slidably through an opening 51 in the bottom of the cup member 49 and which has a head 52 slidably disposed within said cup member. An expansion coil spring 53 is contained in the cup member 49 between the upper closed end of the recess 48 and the head 52 for urging the pin 50 downwardly and outwardly of the cup member 49 and into seating engagement with a central recess 46a in the top surface 46 of the valve, to thereby maintain the vacuum cup 44 in a centered position on the valve. The extension shaft 39 may be of any length or extension shafts of different lengths may be provided. The suction cup 44 and the parts carried thereby may be dispensed with and the extension shaft 39 may be provided with a bit end corresponding to a screw driver bit, not shown, in lieu of the portion 42, for engaging a kerf in the upper surface of the valve head, as is conventional.

The valve grinding attachment 6 is connected to the drill chuck 37, as illustrated in Figure 2, and the suction cup 44 is engaged with the upper surface 46 of the valve head. The operator grasps the handle 38 with one hand and the handle of the electric drill with the other and energizes the electric drill in a conventional manner for driving the input shaft 20. The pinion 23 rotates with the input shaft to revolve the ring gear 29. The crankpin 34 by engagement with the slot 33 causes an oscillating motion to be imparted to the arm 32 and gear segment 30 from the ring gear 29. The gear segment 30 in turn oscillates the pinion 24, the output shaft 21, the shaft extension 39 and the vacuum cup 44 for oscillating the valve 47 for grinding the surface 54 thereof and the valve seat 55. During this operation, the grinding attachment 6 is swung by the handle 38, turning about the axis of the shafts 20 and 21 to thereby insure that the starting and stopping positions of the grinding operation will be at different circumferential points relative to the surfaces 54 and 55. In this manner an overlapping of the starting and stopping positions of the grinding operation may be accomplished to obtain a more accurate and uniform grinding of the surfaces 54 and 55. The grinder 6 may also be swung, as previously described, while the input shaft 20 is not rotating to effect an overlapping of a previous stopping position of a prior partial grinding operation. It will also be apparent that the disposition of the handle 38 relative to the axis of rotation of the input and output shafts 20 and 21 will enable the grinding attachment 6 to be held steady during the grinding operation and while the attachment is being swung or oscillated by its handle 38 to maintain the shafts 20 and 21 in positions substantially perpendicular to the valve surface 46 to maintain the proper engagement between the attachment 6 and the valve head 47.v

'gear into oscillating motion of It will also be noted that when the attachment is in use a pressure is exerted downwardly on the input shaft 20 and an upward thrust is exerted on the output shaft 21. The pairs of nuts 36 will restrict inward displacement of these shafts relative to the housing 7 so that the pinions 23 and 24 will be maintained in properly spaced relation to one another and in positions coplanar with the gear 29 and gear segment 30, respectively, for proper meshing engagement of the pinions with said gears.

Various modifications and changes are contemplated and may obviously be resorted to, without departing from the spirit or scope of the invention as hereinafter defined by the appended claim.

I claim as my invention:

A valve grinding attachment of the character described comprising a housing provided with aligned bearings, an input shaft journalled in one of said bearings, an output shaft journalled in the other bearing, pinions fixed to adjacent ends of said shafts and disposed for rotation within the housing, a gear journalled in said housing and disposed in meshing engagement with the input shaft pinion, a gear segment journalled in said housing and meshing with the output shaft pinion, an arm forming an extension of said gear segment, said arm having an elongated slot extending substantially radially from the axis of rotation of the gear segment, and a crankpin fixed to said gear and disposed eccentrically thereof, said crankpin loosely engaging in said slot for converting the rotary motion of the said gear segment whereby said output shaft will be oscillated by rotation of the input shaft, said input and output shafts having remote ends disposed externally of the housing, said remote end of the input shaft being adapted to be connected to and rotated with an electric drill chuck, and means connected to said remote end of the output shaft and adapted to be detachably connected to a valve for causing said valve to be oscillated with the output shaft.

References Cited in the file of this patent UNITED STATES PATENTS 

